The Present Disclosure generally relates to optical fiber connectors and, more particularly, to connectors with improved latching structure and duplex clip.
Optical fiber connectors are an essential part of substantially any optical fiber based communication system. For instance, such connectors may be used to join segments of fiber into longer lengths, to connect fiber to active devices such as transceivers, detectors and repeaters, or to connect fiber to passive devices such as switches and attenuators. The central function of an optical fiber connector is to maintain or position two optical fiber ends such that the core of one fiber is axially aligned with the core of the other fiber. Consequently, the light from one fiber is coupled to the other fiber or transferred between the fibers as efficiently as possible. This is a particularly challenging task because the light-carrying region or core of an optical fiber is quite small. In single mode optical fibers, the core diameter is about 9 microns. In multi-mode fibers, the core can be as large as 62.5 to 100 microns and, hence, alignment is less critical. However, precise alignment is still a necessary feature to effectively interconnect the optical fibers.
Another function of an optical fiber connector is to provide mechanical stability to and protection for the optical junction in its working environment. Achieving low insertion loss in coupling two optical fibers is generally a function of the alignment of the fiber ends, the width of the gap between the ends, and the optical surface condition of either or both ends.
Precise alignment of the optical fiber is typically accomplished within the design of the optical terminus assembly. The typical optical terminus assembly includes a small cylindrical metal or ceramic ferrule at one end that has a high precision hole passing through its central axis. Glass or plastic optical fiber is secured within the hole of the ferrule using mechanical, adhesive or other retention methods.
In a connection between a pair of optical fibers, the ferrules are butted together in an end-to-end manner and light travels from one to the other along their common central axis.
In order to minimize the loss of light caused by the connection, it is highly desirable for the cores of the glass fibers to be precisely aligned. The ferrules are typically part of a spring loaded assembly that is movable along the central axis of the optical fibers. Upon mating, each ferrule typically moves approximately 0.5 mm away from its unmated position.
In order to expand the range of applications in which optical fiber connectors may be used, plastic housings are sometimes replaced with metal in order to permit the use of optical fiber connectors in extreme temperature, chemical or other environmental conditions. However, such metal housings create challenges relative to the latching structure between components containing the ferrules due to the high precision required and the relatively small distances the ferrules move when mated. That is, metal latch design and construction are challenging in several aspects. First, unlike the plastic housing-latch construction, the metal latch is typically a separate part that must be mounted to housing. Second, a metal latch has its own bending characteristics, which tends to be less stable than that of a plastic latch. Accordingly, additional measures are necessary to ensure that metal latches function correctly.